depbw



UNITED STATES PATENT FFICE.

JOHN H. DEPEW, OF PEEKSKILL, NEW YORK, ASSIGNOR TO HIMSELF AND WILLIAMH. DEPEW, OF SAME PLACE.

SPRUE FOR FOUNDRY USE.

SPECIFICATION forming part of Letters Patent No. 275,332, dated April 3,1883.

Application filed October 4, 1882. No model.)

.To all whom it may concern:

Be it known that l, JOHN H, DEPEW, of Peekskill, in the county ofWestehester and State of New York, have invented certain new and usefulImprovements relating to Sprues for Foundry Use; and I do hereby declarethat the following is full and exact description thereof.

The invention consists in making elastic or yielding the whole or aportion of the pin or wedge serving as the sprue, and which, by itspresence, forms the aperture through which the melted-metal is poured toreach the proper cavity in the mold, so that an accidental blow 1.5received from the rammer in compacting the material of the mold will notbreak the pattern or seriously disturb the work. The term sprue isapplied indifi'erently by some molders to the hole in the molding-sandthrough which the hot metal is poured, the pattern which makes suchhole, and the useless molded mass of metal which remains and hardens inthe hole. I will use the term as applied to the pattern which molds thehole. It is common to make the pin or wedge serving as the sprue of woodor metal. The molding-sand requires to be compacted around the patternand around the sprue by strong blows with a heavy rammer. With ordinarycare and skill it is difficult to avoid hitting the sprue-occasionallywith the rammer. To avoid mischief from this source it is common toplace the sprues out of contact with the pattern. They extend from oneof the outer faces of the mold to the parting-joint between two parts ofthe mold. From the sprue to the mold a sufficient channel is made byother means, and the passage is differently named, being usually termedthe gate. My invention is not vitally important where the mold, from'itsnature, can be sprued and gated in that manner; but there is a largeclass of work in which'it is essential to success that the hot metal bedelivered into the pattern-cavity as directly as possible. Stovecastingsform a large class of such work. The metal, if received through thesprue and gate at one side of the pattern, would be likely to freezebefore flowing through the thin space in the cold sand to theextremecorners of the cav- 50 ity. For such castings it is common to useone or more wedge-shaped sprues,and to connect it or them by placing itdirectly on the pattern, so that the metal will be received through thesprue directly into the pattern cavity near its center, and will flowrapidly in all directions therefrom. Anotherlargeaudincreasingclass ofmolding is the manufacture of butt-hinges and analogous small separatearticles in the large way by molding large numbers in a single flask.These may be sprued iu'the ordi- 6o nary way at a point outside of anyof the patterns, and several gates may extend from one sprue to six orother number of the. mold-cavities. To economize labor and insure a justsufthe gates by means of a brass or iron pattern of proper form. Thesprue then rests on the pattern for the gate. The molder,iumanufacturing either of these classes of work, finds his sprue restingdirectly on a hard and delicate 7o object. A blow of the ramniertouching the sprue is liable to fracture or bend the gatepattern in thelatter class, and the still more precious stove-plate pattern or otherelaborately-wrought pattern on which the sprue rests in the lastpreceding class. I avoid the mischief by making the whole sprue, or aprincipal portion thereof, of indie-rubber or analogous yieldingmaterial. In order to preserve the proper form, and the small size ofthe junctare in the stove-plate and analogous class of castings, I use awedge-shaped sprue mainly of indie-rubber, but with the thin end of thewedge formed entirely or shod with metal.

My yielding sprue works in all respects like the ordinary rigid ones,except when it is struck by the rammer. Then, instead of transmittingthe blow with great force through itself to the delicate gate-pattern orother pattern below, it simply yields by compression c and bending. Itis liable to increase the size of the sprue-passage at the upper end,and to deform its contour; but that is anevil so slight as to beinsignificant. The lower end of the point is of exactly the proper sizeand form. N o injurious shock is communicated to the lower end of thesprue-pattern, and no serious blow is felt by'the pattern on which thesprue rests.

ficiently eapacious gate, it is common to mold 65- sprue remainsunaffected, and the hole at that 5 The accompanying drawings form a partof this specification, and represent what I consider the best means ofcarrying out the invention.

Figure 1 is an edge view, partly in section. Fig. 2 is a side view of myimproved sprue.

Similar letters of reference indicate corresponding parts in both thefigures.

A is the main body of the sprue, of rubber, or some compound of whichrubber is a component. It may be either vulcanized or unvulcanized; butit is important that it be soft and yielding.

B is a shoe, of rolled brass or other suitable metal or materiahfittedupon the end which is to come in contact with thepattern. The metal B issunk into the rubberA so that the exterior surfaces are flush. O arerivets holding the parts reliably together. The metal portion B is moreespecially important on thinended or wedge-shaped sprues. It is commonfor molders to remove a portion of the molding-sand immediately at thepoint or narrowest portion of such sprues. The softness of the materialwhich I prefer to employ for the main body illy adapts it to endure manyrepetitions of the molding process with the thin portion of the spruenndefended but with my metal shoe the thinnest end ever required on asprue may be maintained in good condition for an indefinite period.

Modifications may be made in the forms and proportions. Parts of theinvention may be used without the whole. I can for some sprues omit themetal portion B. I can make the metal portion of cast or forged metalinstead of sheet metal, as indicated.

Instead of rubber or its compounds as th material for the main portionA, I can use gutta-percha, and various other gums and elastic compounds;or I can use felt or analogous yielding material, either bare or coatedwith oil or paint, or with a fabricas oilcloth-or with other yieldingcoating which shall be sufficiently smooth to allow the sprue to bedrawn from the sand.

I do not esteem it absolutely essential to success that the material Ashall be elastic, in the ordinary sense of the term. It is sufiicient ifit be simply soft. A casing of oilcloth, gut, or other smooth material,tilled with sand, bran, or other yielding material, may be e made toserve. I prefer soft vulcanized rubher, compounded, molded, andvulcanized in the manner in which that material is usually worked.

I claim as my invention 1. A sprue having its main body A of rubber orother yielding material, and a form and surface adapted to be drawn fromthe sand, all substantially as herein specified.

2. The compound sprue described, having a body, A, of yielding material,and a shoe, B, of hard material, combined as shown, and having a formand substance adapted to be drawn from the sand, all substantially asand for the purposes herein specified.

In testimony whereof I have hereunto set my hand, at Peekskill, this30th day of September, 1882, in the presence of two subsoribin gwitnesses.

JOHN H. DEPEW.

Witnesses: I

A. W. WYATT, ISAAC LosEE.

